From 297101c3f869abe02aeb642774f6c82b75fcfe81 Mon Sep 17 00:00:00 2001 From: Max Kellermann Date: Fri, 30 Jan 2009 00:07:53 +0100 Subject: input_stream: documented the API --- src/input_stream.h | 92 ++++++++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 83 insertions(+), 9 deletions(-) (limited to 'src/input_stream.h') diff --git a/src/input_stream.h b/src/input_stream.h index 5761adc1..f57ac312 100644 --- a/src/input_stream.h +++ b/src/input_stream.h @@ -37,33 +37,92 @@ struct input_plugin { }; struct input_stream { + /** + * the plugin which implements this input stream + */ const struct input_plugin *plugin; - bool seekable; + /** + * an opaque pointer managed by the plugin + */ + void *data; + + /** + * indicates whether the stream is ready for reading and + * whether the other attributes in this struct are valid + */ bool ready; + /** + * if true, then the stream is fully seekable + */ + bool seekable; + + /** + * an optional errno error code, set to non-zero after an error occured + */ int error; - off_t size, offset; - char *mime; - void *data; + /** + * the size of the resource, or -1 if unknown + */ + off_t size; + + /** + * the current offset within the stream + */ + off_t offset; + + /** + * the MIME content type of the resource, or NULL if unknown + */ + char *mime; void *archive; }; +/** + * Initializes this library and all input_stream implementations. + */ void input_stream_global_init(void); +/** + * Deinitializes this library and all input_stream implementations. + */ void input_stream_global_finish(void); -/* if an error occurs for these 3 functions, then -1 is returned and errno - for the input stream is set */ +/** + * Opens a new input stream. You may not access it until the "ready" + * flag is set. + * + * @param is the input_stream object allocated by the caller + * @return true on success + */ bool input_stream_open(struct input_stream *is, const char *url); +/** + * Closes the input stream and free resources. This does not free the + * input_stream pointer itself, because it is assumed to be allocated + * by the caller. + */ +void +input_stream_close(struct input_stream *is); + +/** + * Seeks to the specified position in the stream. This will most + * likely fail if the "seekable" flag is false. + * + * @param is the input_stream object + * @param offset the relative offset + * @param whence the base of the seek, one of SEEK_SET, SEEK_CUR, SEEK_END + */ bool input_stream_seek(struct input_stream *is, off_t offset, int whence); -void input_stream_close(struct input_stream *is); +/** + * Returns true if the stream has reached end-of-file. + */ bool input_stream_eof(struct input_stream *is); /** @@ -75,10 +134,25 @@ bool input_stream_eof(struct input_stream *is); struct tag * input_stream_tag(struct input_stream *is); -/* return value: -1 is error, 1 inidicates stuff was buffered, 0 means nothing - was buffered */ +/** + * Reads some of the stream into its buffer. The following return + * codes are defined: -1 = error, 1 = something was buffered, 0 = + * nothing was buffered. + * + * The semantics of this function are not well-defined, and it will + * eventually be removed. + */ int input_stream_buffer(struct input_stream *is); +/** + * Reads data from the stream into the caller-supplied buffer. + * Returns 0 on error or eof (check with input_stream_eof()). + * + * @param is the input_stream object + * @param ptr the buffer to read into + * @param size the maximum number of bytes to read + * @return the number of bytes read + */ size_t input_stream_read(struct input_stream *is, void *ptr, size_t size); -- cgit v1.2.3